diff --git a/src/query/src/qFilter.c b/src/query/src/qFilter.c
index 6d06d8e3cd0423a71d2cc030b1d87003416dcb05..45661ee98295144b70209da242c4d7613e76a324 100644
--- a/src/query/src/qFilter.c
+++ b/src/query/src/qFilter.c
@@ -1573,7 +1573,7 @@ void filterDumpInfoToString(SFilterInfo *info, const char *msg, int32_t options)
             tlen = varDataLen(data);
             data += VARSTR_HEADER_SIZE;
           }
-          converToStr(str + len, type, data, tlen > 32 ? 32 : tlen, &tlen);
+          if (data) converToStr(str + len, type, data, tlen > 32 ? 32 : tlen, &tlen);
         } else {
           strcat(str, "NULL");
         }